diff --git a/chromecast/browser/BUILD.gn b/chromecast/browser/BUILD.gn
index 62676a44db65d8..7e0c34e4fda3b5 100644
--- a/chromecast/browser/BUILD.gn
+++ b/chromecast/browser/BUILD.gn
@@ -99,8 +99,6 @@ cast_source_set("browser") {
     "cast_web_contents_impl.h",
     "cast_web_service.cc",
     "cast_web_service.h",
-    "cast_web_view_base.cc",
-    "cast_web_view_base.h",
     "cast_web_view_default.cc",
     "cast_web_view_default.h",
     "cast_web_view_factory.cc",
diff --git a/chromecast/browser/cast_content_window_aura.cc b/chromecast/browser/cast_content_window_aura.cc
index f0da6a28d0d21b..068cae6435c536 100644
--- a/chromecast/browser/cast_content_window_aura.cc
+++ b/chromecast/browser/cast_content_window_aura.cc
@@ -79,8 +79,7 @@ CastContentWindowAura::CastContentWindowAura(
       gesture_priority_(params.gesture_priority),
       is_touch_enabled_(params.enable_touch_input),
       window_(nullptr),
-      has_screen_access_(false),
-      resize_window_when_navigation_starts_(true) {}
+      has_screen_access_(false) {}
 
 CastContentWindowAura::~CastContentWindowAura() {
   CastWebContents::Observer::Observe(nullptr);
@@ -100,7 +99,6 @@ void CastContentWindowAura::CreateWindowForWebContents(
   DCHECK(window_manager_) << "A CastWindowManager must be provided before "
                           << "creating a window for WebContents.";
   CastWebContents::Observer::Observe(cast_web_contents);
-  content::WebContentsObserver::Observe(cast_web_contents->web_contents());
   window_ = cast_web_contents->web_contents()->GetNativeView();
   if (!window_->HasObserver(this)) {
     window_->AddObserver(this);
@@ -133,7 +131,6 @@ void CastContentWindowAura::GrantScreenAccess() {
 
 void CastContentWindowAura::RevokeScreenAccess() {
   has_screen_access_ = false;
-  resize_window_when_navigation_starts_ = false;
   if (window_) {
     window_->Hide();
     // Because rendering a larger window may require more system resources,
@@ -191,23 +188,4 @@ void CastContentWindowAura::OnWindowDestroyed(aura::Window* window) {
   window_ = nullptr;
 }
 
-void CastContentWindowAura::DidStartNavigation(
-    content::NavigationHandle* navigation_handle) {
-  if (!resize_window_when_navigation_starts_) {
-    return;
-  }
-  resize_window_when_navigation_starts_ = false;
-
-  // Resize window
-  gfx::Size display_size =
-      display::Screen::GetScreen()->GetPrimaryDisplay().size();
-  aura::Window* content_window = web_contents()->GetNativeView();
-  content_window->SetBounds(
-      gfx::Rect(display_size.width(), display_size.height()));
-}
-
-void CastContentWindowAura::WebContentsDestroyed() {
-  content::WebContentsObserver::Observe(nullptr);
-}
-
 }  // namespace chromecast
diff --git a/chromecast/browser/cast_content_window_aura.h b/chromecast/browser/cast_content_window_aura.h
index 6379810a057333..bff975c2d02511 100644
--- a/chromecast/browser/cast_content_window_aura.h
+++ b/chromecast/browser/cast_content_window_aura.h
@@ -9,8 +9,6 @@
 #include "chromecast/browser/cast_content_gesture_handler.h"
 #include "chromecast/browser/cast_content_window.h"
 #include "chromecast/ui/media_control_ui.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/browser/web_contents_observer.h"
 #include "ui/aura/window_observer.h"
 
 namespace aura {
@@ -23,7 +21,6 @@ class TouchBlocker;
 
 class CastContentWindowAura : public CastContentWindow,
                               public CastWebContents::Observer,
-                              private content::WebContentsObserver,
                               public aura::WindowObserver {
  public:
   CastContentWindowAura(const CastContentWindow::CreateParams& params,
@@ -53,11 +50,6 @@ class CastContentWindowAura : public CastContentWindow,
   void OnWindowDestroyed(aura::Window* window) override;
 
  private:
-  // WebContentsObserver implementation:
-  void DidStartNavigation(
-      content::NavigationHandle* navigation_handle) override;
-  void WebContentsDestroyed() override;
-
   CastWindowManager* const window_manager_;
 
   // Utility class for detecting and dispatching gestures to delegates.
@@ -71,7 +63,6 @@ class CastContentWindowAura : public CastContentWindow,
 
   aura::Window* window_;
   bool has_screen_access_;
-  bool resize_window_when_navigation_starts_;
 
   DISALLOW_COPY_AND_ASSIGN(CastContentWindowAura);
 };
diff --git a/chromecast/browser/cast_web_contents.h b/chromecast/browser/cast_web_contents.h
index a4df057ab568b6..11559a1d6144ca 100644
--- a/chromecast/browser/cast_web_contents.h
+++ b/chromecast/browser/cast_web_contents.h
@@ -295,18 +295,6 @@ class CastWebContents {
   // page.
   virtual void Stop(int error_code) = 0;
 
-  // ===========================================================================
-  // Visibility
-  // ===========================================================================
-
-  // Specify if the WebContents should be treated as visible. This triggers a
-  // document "visibilitychange" change event, and will paint the WebContents
-  // quad if |visible| is true (otherwise it will be blank). Note that this does
-  // *not* guarantee the page is visible on the screen, as that depends on if
-  // the WebContents quad is present in the screen layout and isn't obscured by
-  // another window.
-  virtual void SetWebVisibilityAndPaint(bool visible) = 0;
-
   // ===========================================================================
   // Media Management
   // ===========================================================================
diff --git a/chromecast/browser/cast_web_contents_impl.cc b/chromecast/browser/cast_web_contents_impl.cc
index 874be2e13cb465..7dd83daccec7b9 100644
--- a/chromecast/browser/cast_web_contents_impl.cc
+++ b/chromecast/browser/cast_web_contents_impl.cc
@@ -290,21 +290,6 @@ void CastWebContentsImpl::Stop(int error_code) {
   NotifyPageState();
 }
 
-void CastWebContentsImpl::SetWebVisibilityAndPaint(bool visible) {
-  if (!web_contents_)
-    return;
-  if (visible) {
-    web_contents_->WasShown();
-  } else {
-    web_contents_->WasHidden();
-  }
-  if (web_contents_->GetVisibility() != content::Visibility::VISIBLE) {
-    // Since we are managing the visibility, we need to ensure pages are
-    // unfrozen in the event this occurred while in the background.
-    web_contents_->SetPageFrozen(false);
-  }
-}
-
 void CastWebContentsImpl::BlockMediaLoading(bool blocked) {
   if (media_blocker_)
     media_blocker_->BlockMediaLoading(blocked);
diff --git a/chromecast/browser/cast_web_contents_impl.h b/chromecast/browser/cast_web_contents_impl.h
index accde3b2232f8e..165dabfe86fc18 100644
--- a/chromecast/browser/cast_web_contents_impl.h
+++ b/chromecast/browser/cast_web_contents_impl.h
@@ -59,7 +59,6 @@ class CastWebContentsImpl : public CastWebContents,
   void LoadUrl(const GURL& url) override;
   void ClosePage() override;
   void Stop(int error_code) override;
-  void SetWebVisibilityAndPaint(bool visible) override;
   void RegisterInterfaceProvider(
       const InterfaceSet& interface_set,
       service_manager::InterfaceProvider* interface_provider) override;
diff --git a/chromecast/browser/cast_web_service.cc b/chromecast/browser/cast_web_service.cc
index 5ed2454e44cfa6..882598707adb8b 100644
--- a/chromecast/browser/cast_web_service.cc
+++ b/chromecast/browser/cast_web_service.cc
@@ -17,11 +17,11 @@
 #include "base/time/time.h"
 #include "chromecast/browser/cast_web_view_default.h"
 #include "chromecast/browser/cast_web_view_factory.h"
-#include "chromecast/browser/lru_renderer_cache.h"
 #include "chromecast/chromecast_buildflags.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/gpu_utils.h"
 #include "content/public/browser/media_session.h"
+#include "content/public/browser/site_instance.h"
 #include "content/public/browser/storage_partition.h"
 #include "content/public/browser/web_contents.h"
 #include "services/network/public/mojom/cookie_manager.mojom.h"
@@ -46,8 +46,6 @@ CastWebService::CastWebService(content::BrowserContext* browser_context,
     : browser_context_(browser_context),
       web_view_factory_(web_view_factory),
       window_manager_(window_manager),
-      overlay_renderer_cache_(
-          std::make_unique<LRURendererCache>(browser_context_, 1)),
       task_runner_(base::SequencedTaskRunnerHandle::Get()),
       weak_factory_(this) {
   DCHECK(browser_context_);
@@ -60,9 +58,26 @@ CastWebService::~CastWebService() = default;
 
 CastWebView::Scoped CastWebService::CreateWebView(
     const CastWebView::CreateParams& params,
+    scoped_refptr<content::SiteInstance> site_instance,
     const GURL& initial_url) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  auto web_view = web_view_factory_->CreateWebView(params, this, initial_url);
+  auto web_view = web_view_factory_->CreateWebView(
+      params, this, std::move(site_instance), initial_url);
+  CastWebView::Scoped scoped(web_view.get(), [this](CastWebView* web_view) {
+    OwnerDestroyed(web_view);
+  });
+  web_views_.insert(std::move(web_view));
+  return scoped;
+}
+
+CastWebView::Scoped CastWebService::CreateWebView(
+    const CastWebView::CreateParams& params,
+    const GURL& initial_url) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  auto web_view = web_view_factory_->CreateWebView(
+      params, this,
+      content::SiteInstance::CreateForURL(browser_context_, initial_url),
+      initial_url);
   CastWebView::Scoped scoped(web_view.get(), [this](CastWebView* web_view) {
     OwnerDestroyed(web_view);
   });
diff --git a/chromecast/browser/cast_web_service.h b/chromecast/browser/cast_web_service.h
index dea0c11f55a762..fb6328a67a00f8 100644
--- a/chromecast/browser/cast_web_service.h
+++ b/chromecast/browser/cast_web_service.h
@@ -28,7 +28,6 @@ namespace chromecast {
 
 class CastWebViewFactory;
 class CastWindowManager;
-class LRURendererCache;
 
 // This class dispenses CastWebView objects which are used to wrap WebContents
 // in cast_shell. This class temporarily takes ownership of CastWebViews when
@@ -42,17 +41,17 @@ class CastWebService {
                  CastWindowManager* window_manager);
   ~CastWebService();
 
+  CastWebView::Scoped CreateWebView(
+      const CastWebView::CreateParams& params,
+      scoped_refptr<content::SiteInstance> site_instance,
+      const GURL& initial_url);
+
   CastWebView::Scoped CreateWebView(const CastWebView::CreateParams& params,
                                     const GURL& initial_url);
 
   std::unique_ptr<CastContentWindow> CreateWindow(
       const CastContentWindow::CreateParams& params);
 
-  content::BrowserContext* browser_context() { return browser_context_; }
-  LRURendererCache* overlay_renderer_cache() {
-    return overlay_renderer_cache_.get();
-  }
-
   void FlushDomLocalStorage();
 
   // |callback| is called when data deletion is done or at least the deletion
@@ -69,8 +68,6 @@ class CastWebService {
   CastWindowManager* const window_manager_;
   base::flat_set<std::unique_ptr<CastWebView>> web_views_;
 
-  const std::unique_ptr<LRURendererCache> overlay_renderer_cache_;
-
   const scoped_refptr<base::SequencedTaskRunner> task_runner_;
   base::WeakPtr<CastWebService> weak_ptr_;
 
diff --git a/chromecast/browser/cast_web_view.cc b/chromecast/browser/cast_web_view.cc
index f6775bb1a43804..5f6e9d4d97811c 100644
--- a/chromecast/browser/cast_web_view.cc
+++ b/chromecast/browser/cast_web_view.cc
@@ -13,10 +13,31 @@ CastWebView::Delegate::RunBluetoothChooser(
   return nullptr;
 }
 
-CastWebView::CreateParams::CreateParams() = default;
+CastWebView::CastWebView(const CreateParams& create_params)
+    : delegate_(create_params.delegate),
+      shutdown_delay_(create_params.shutdown_delay) {}
 
-CastWebView::CreateParams::CreateParams(const CreateParams& other) = default;
+CastWebView::~CastWebView() {
+  for (Observer& observer : observer_list_) {
+    observer.OnPageDestroyed(this);
+  }
+}
 
+void CastWebView::ForceClose() {
+  shutdown_delay_ = base::TimeDelta();
+  ClosePage();
+}
+
+void CastWebView::AddObserver(CastWebView::Observer* observer) {
+  observer_list_.AddObserver(observer);
+}
+
+void CastWebView::RemoveObserver(CastWebView::Observer* observer) {
+  observer_list_.RemoveObserver(observer);
+}
+
+CastWebView::CreateParams::CreateParams() = default;
+CastWebView::CreateParams::CreateParams(const CreateParams& other) = default;
 CastWebView::CreateParams::~CreateParams() = default;
 
 }  // namespace chromecast
diff --git a/chromecast/browser/cast_web_view.h b/chromecast/browser/cast_web_view.h
index 2c83c2ded6f336..6ca15a35fb4e83 100644
--- a/chromecast/browser/cast_web_view.h
+++ b/chromecast/browser/cast_web_view.h
@@ -9,8 +9,10 @@
 #include <string>
 
 #include "base/macros.h"
+#include "base/observer_list.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
+#include "base/values.h"
 #include "chromecast/browser/cast_content_window.h"
 #include "chromecast/browser/cast_web_contents.h"
 #include "chromecast/ui/mojom/ui_service.mojom.h"
@@ -20,8 +22,6 @@
 
 namespace chromecast {
 
-class CastWebService;
-
 // A simplified interface for loading and displaying WebContents in cast_shell.
 class CastWebView {
  public:
@@ -55,14 +55,6 @@ class CastWebView {
   using Scoped =
       std::unique_ptr<CastWebView, std::function<void(CastWebView*)>>;
 
-  enum class RendererPool {
-    // Don't use a renderer pool for prelaunching. This means launching the
-    // render process eagerly is un-restricted and will always succeed.
-    NONE,
-    // Pool for overlay apps, which allows up to one pre-cached site.
-    OVERLAY,
-  };
-
   // The parameters used to create a CastWebView instance. Passed to
   // CastWebService::CreateWebView().
   struct CreateParams {
@@ -79,8 +71,6 @@ class CastWebView {
     // Parameters for creating the content window for this CastWebView.
     CastContentWindow::CreateParams window_params;
 
-    CastWebService* web_service = nullptr;
-
     // Identifies the activity that is hosted by this CastWebView.
     std::string activity_id = "";
 
@@ -105,19 +95,13 @@ class CastWebView {
     // immediately and synchronously.
     base::TimeDelta shutdown_delay = base::TimeDelta();
 
-    // Pool for pre-launched renderers.
-    RendererPool renderer_pool = RendererPool::NONE;
-
-    // Eagerly pre-launches a render process for |prelaunch_url| if it is valid.
-    GURL prelaunch_url;
-
     CreateParams();
     CreateParams(const CreateParams& other);
     ~CreateParams();
   };
 
-  CastWebView() = default;
-  virtual ~CastWebView() = default;
+  explicit CastWebView(const CreateParams& create_params);
+  virtual ~CastWebView();
 
   virtual CastContentWindow* window() const = 0;
 
@@ -125,10 +109,21 @@ class CastWebView {
 
   virtual CastWebContents* cast_web_contents() = 0;
 
-  virtual base::TimeDelta shutdown_delay() const = 0;
+  base::TimeDelta shutdown_delay() const { return shutdown_delay_; }
+
+  // Navigates to |url|. The loaded page will be preloaded if MakeVisible has
+  // not been called on the object.
+  virtual void LoadUrl(GURL url) = 0;
+
+  // Begins the close process for this page (ie. triggering document.onunload).
+  // A consumer of the class can be notified when the process has been finished
+  // via Delegate::OnPageStopped(). The page will be torn down after
+  // |CreateParams::shutdown_delay| has elapsed, or immediately if the browser
+  // is shutting down.
+  virtual void ClosePage() = 0;
 
   // Closes the page immediately, ignoring |CreateParams::shutdown_delay|.
-  virtual void ForceClose() = 0;
+  void ForceClose();
 
   // Adds the page to the window manager and makes it visible to the user if
   // |is_visible| is true. |z_order| determines how this window is layered in
@@ -136,11 +131,26 @@ class CastWebView {
   virtual void InitializeWindow(mojom::ZOrder z_order,
                                 VisibilityPriority initial_priority) = 0;
 
+  // Allows the page to be shown on the screen. The page cannot be shown on the
+  // screen until this is called.
+  virtual void GrantScreenAccess() = 0;
+
+  // Prevents the page from being shown on the screen until GrantScreenAccess()
+  // is called.
+  virtual void RevokeScreenAccess() = 0;
+
   // Observer interface:
-  virtual void AddObserver(Observer* observer) = 0;
-  virtual void RemoveObserver(Observer* observer) = 0;
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+ protected:
+  base::WeakPtr<Delegate> delegate_;
 
  private:
+  base::TimeDelta shutdown_delay_;
+
+  base::ObserverList<Observer>::Unchecked observer_list_;
+
   DISALLOW_COPY_AND_ASSIGN(CastWebView);
 };
 
diff --git a/chromecast/browser/cast_web_view_base.cc b/chromecast/browser/cast_web_view_base.cc
deleted file mode 100644
index db4ca23e5245bd..00000000000000
--- a/chromecast/browser/cast_web_view_base.cc
+++ /dev/null
@@ -1,68 +0,0 @@
-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chromecast/browser/cast_web_view_base.h"
-
-#include "chromecast/browser/cast_web_service.h"
-#include "chromecast/browser/lru_renderer_cache.h"
-#include "chromecast/browser/renderer_prelauncher.h"
-#include "content/public/browser/site_instance.h"
-
-namespace chromecast {
-
-CastWebViewBase::CastWebViewBase(const CreateParams& create_params,
-                                 CastWebService* web_service)
-    : delegate_(create_params.delegate),
-      web_service_(web_service),
-      shutdown_delay_(create_params.shutdown_delay),
-      renderer_pool_(create_params.renderer_pool),
-      prelaunch_url_(create_params.prelaunch_url),
-      renderer_prelauncher_(nullptr),
-      site_instance_(nullptr) {
-  DCHECK(web_service_);
-  if (prelaunch_url_.is_valid()) {
-    if (renderer_pool_ == RendererPool::OVERLAY) {
-      renderer_prelauncher_ =
-          web_service_->overlay_renderer_cache()->TakeRendererPrelauncher(
-              prelaunch_url_);
-    } else {
-      renderer_prelauncher_ = std::make_unique<RendererPrelauncher>(
-          web_service_->browser_context(), prelaunch_url_);
-    }
-  }
-  if (renderer_prelauncher_) {
-    renderer_prelauncher_->Prelaunch();
-    site_instance_ = renderer_prelauncher_->site_instance();
-  }
-}
-
-CastWebViewBase::~CastWebViewBase() {
-  if (renderer_prelauncher_ && prelaunch_url_.is_valid() &&
-      renderer_pool_ == RendererPool::OVERLAY) {
-    web_service_->overlay_renderer_cache()->ReleaseRendererPrelauncher(
-        prelaunch_url_);
-  }
-  for (Observer& observer : observer_list_) {
-    observer.OnPageDestroyed(this);
-  }
-}
-
-void CastWebViewBase::ForceClose() {
-  shutdown_delay_ = base::TimeDelta();
-  cast_web_contents()->ClosePage();
-}
-
-void CastWebViewBase::AddObserver(CastWebViewBase::Observer* observer) {
-  observer_list_.AddObserver(observer);
-}
-
-void CastWebViewBase::RemoveObserver(CastWebViewBase::Observer* observer) {
-  observer_list_.RemoveObserver(observer);
-}
-
-base::TimeDelta CastWebViewBase::shutdown_delay() const {
-  return shutdown_delay_;
-}
-
-}  // namespace chromecast
diff --git a/chromecast/browser/cast_web_view_base.h b/chromecast/browser/cast_web_view_base.h
deleted file mode 100644
index 9da7e7140584af..00000000000000
--- a/chromecast/browser/cast_web_view_base.h
+++ /dev/null
@@ -1,63 +0,0 @@
-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CHROMECAST_BROWSER_CAST_WEB_VIEW_BASE_H_
-#define CHROMECAST_BROWSER_CAST_WEB_VIEW_BASE_H_
-
-#include <cstdint>
-#include <memory>
-
-#include "base/memory/scoped_refptr.h"
-#include "base/memory/weak_ptr.h"
-#include "base/observer_list.h"
-#include "base/time/time.h"
-#include "chromecast/browser/cast_web_view.h"
-#include "url/gurl.h"
-
-namespace content {
-class SiteInstance;
-}  // namespace content
-
-namespace chromecast {
-
-class CastWebService;
-class RendererPrelauncher;
-
-// Common logic for CastWebView implementations.
-class CastWebViewBase : public CastWebView {
- public:
-  CastWebViewBase(const CreateParams& create_params,
-                  CastWebService* web_service);
-  CastWebViewBase(const CastWebViewBase&) = delete;
-  CastWebViewBase& operator=(const CastWebViewBase&) = delete;
-  ~CastWebViewBase() override;
-
-  scoped_refptr<content::SiteInstance> site_instance() const {
-    return site_instance_;
-  }
-
-  // CastWebView implementation (partial):
-  void ForceClose() override;
-  void AddObserver(Observer* observer) override;
-  void RemoveObserver(Observer* observer) override;
-  base::TimeDelta shutdown_delay() const override;
-
- protected:
-  base::WeakPtr<Delegate> delegate_;
-  CastWebService* const web_service_;
-
- private:
-  base::TimeDelta shutdown_delay_;
-  const RendererPool renderer_pool_;
-  const GURL prelaunch_url_;
-
-  std::unique_ptr<RendererPrelauncher> renderer_prelauncher_;
-  scoped_refptr<content::SiteInstance> site_instance_;
-
-  base::ObserverList<Observer>::Unchecked observer_list_;
-};
-
-}  // namespace chromecast
-
-#endif  // CHROMECAST_BROWSER_CAST_WEB_VIEW_BASE_H_
diff --git a/chromecast/browser/cast_web_view_default.cc b/chromecast/browser/cast_web_view_default.cc
index d4f0ad13b5d48b..b24749c2b10a9b 100644
--- a/chromecast/browser/cast_web_view_default.cc
+++ b/chromecast/browser/cast_web_view_default.cc
@@ -19,6 +19,7 @@
 #include "chromecast/chromecast_buildflags.h"
 #include "content/public/browser/media_capture_devices.h"
 #include "content/public/browser/media_session.h"
+#include "content/public/browser/navigation_handle.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/render_widget_host.h"
@@ -53,23 +54,27 @@ CastWebViewDefault::CastWebViewDefault(
     const CreateParams& params,
     CastWebService* web_service,
     content::BrowserContext* browser_context,
+    scoped_refptr<content::SiteInstance> site_instance,
     std::unique_ptr<CastContentWindow> cast_content_window)
-    : CastWebViewBase(params, web_service),
+    : CastWebView(params),
       web_service_(web_service),
       browser_context_(browser_context),
+      site_instance_(std::move(site_instance)),
       activity_id_(params.activity_id),
       session_id_(params.window_params.session_id),
       sdk_version_(params.sdk_version),
       allow_media_access_(params.allow_media_access),
       log_prefix_(params.log_prefix),
-      web_contents_(CreateWebContents(browser_context_, site_instance())),
+      web_contents_(CreateWebContents(browser_context_, site_instance_)),
       cast_web_contents_(web_contents_.get(), params.web_contents_params),
       window_(cast_content_window
                   ? std::move(cast_content_window)
-                  : web_service->CreateWindow(params.window_params)) {
+                  : web_service->CreateWindow(params.window_params)),
+      resize_window_when_navigation_starts_(true) {
   DCHECK(web_service_);
   DCHECK(browser_context_);
   DCHECK(window_);
+  content::WebContentsObserver::Observe(web_contents_.get());
 
   web_contents_->SetDelegate(this);
 #if defined(USE_AURA)
@@ -99,6 +104,15 @@ CastWebContents* CastWebViewDefault::cast_web_contents() {
   return &cast_web_contents_;
 }
 
+void CastWebViewDefault::LoadUrl(GURL url) {
+  cast_web_contents_.LoadUrl(url);
+}
+
+void CastWebViewDefault::ClosePage() {
+  content::WebContentsObserver::Observe(nullptr);
+  cast_web_contents_.ClosePage();
+}
+
 void CastWebViewDefault::CloseContents(content::WebContents* source) {
   DCHECK_EQ(source, web_contents_.get());
   window_.reset();  // Window destructor requires live web_contents on Android.
@@ -116,6 +130,19 @@ void CastWebViewDefault::InitializeWindow(mojom::ZOrder z_order,
   web_contents_->Focus();
 }
 
+void CastWebViewDefault::GrantScreenAccess() {
+  if (!window_)
+    return;
+  window_->GrantScreenAccess();
+}
+
+void CastWebViewDefault::RevokeScreenAccess() {
+  resize_window_when_navigation_starts_ = false;
+  if (!window_)
+    return;
+  window_->RevokeScreenAccess();
+}
+
 content::WebContents* CastWebViewDefault::OpenURLFromTab(
     content::WebContents* source,
     const content::OpenURLParams& params) {
@@ -254,4 +281,21 @@ bool CastWebViewDefault::ShouldAllowRunningInsecureContent(
   return allowed_per_prefs;
 }
 
+void CastWebViewDefault::DidStartNavigation(
+    content::NavigationHandle* navigation_handle) {
+  if (!resize_window_when_navigation_starts_) {
+    return;
+  }
+  resize_window_when_navigation_starts_ = false;
+
+#if defined(USE_AURA)
+  // Resize window
+  gfx::Size display_size =
+      display::Screen::GetScreen()->GetPrimaryDisplay().size();
+  aura::Window* content_window = web_contents()->GetNativeView();
+  content_window->SetBounds(
+      gfx::Rect(display_size.width(), display_size.height()));
+#endif
+}
+
 }  // namespace chromecast
diff --git a/chromecast/browser/cast_web_view_default.h b/chromecast/browser/cast_web_view_default.h
index b46d7f5180e34a..becf40066ba1e0 100644
--- a/chromecast/browser/cast_web_view_default.h
+++ b/chromecast/browser/cast_web_view_default.h
@@ -13,9 +13,10 @@
 #include "build/build_config.h"
 #include "chromecast/browser/cast_content_window.h"
 #include "chromecast/browser/cast_web_contents_impl.h"
-#include "chromecast/browser/cast_web_view_base.h"
+#include "chromecast/browser/cast_web_view.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_delegate.h"
+#include "content/public/browser/web_contents_observer.h"
 
 namespace content {
 class BrowserContext;
@@ -27,8 +28,9 @@ namespace chromecast {
 class CastWebService;
 
 // A simplified interface for loading and displaying WebContents in cast_shell.
-class CastWebViewDefault : public CastWebViewBase,
-                           private content::WebContentsDelegate {
+class CastWebViewDefault : public CastWebView,
+                           content::WebContentsObserver,
+                           content::WebContentsDelegate {
  public:
   // |web_service| and |browser_context| should outlive this object. If
   // |cast_content_window| is not provided, an instance will be constructed from
@@ -37,6 +39,7 @@ class CastWebViewDefault : public CastWebViewBase,
       const CreateParams& params,
       CastWebService* web_service,
       content::BrowserContext* browser_context,
+      scoped_refptr<content::SiteInstance> site_instance,
       std::unique_ptr<CastContentWindow> cast_content_window = nullptr);
   ~CastWebViewDefault() override;
 
@@ -44,10 +47,18 @@ class CastWebViewDefault : public CastWebViewBase,
   CastContentWindow* window() const override;
   content::WebContents* web_contents() const override;
   CastWebContents* cast_web_contents() override;
+  void LoadUrl(GURL url) override;
+  void ClosePage() override;
   void InitializeWindow(mojom::ZOrder z_order,
                         VisibilityPriority initial_priority) override;
+  void GrantScreenAccess() override;
+  void RevokeScreenAccess() override;
 
  private:
+  // WebContentsObserver implementation:
+  void DidStartNavigation(
+      content::NavigationHandle* navigation_handle) override;
+
   // WebContentsDelegate implementation:
   content::WebContents* OpenURLFromTab(
       content::WebContents* source,
@@ -87,6 +98,7 @@ class CastWebViewDefault : public CastWebViewBase,
   std::unique_ptr<content::WebContents> web_contents_;
   CastWebContentsImpl cast_web_contents_;
   std::unique_ptr<CastContentWindow> window_;
+  bool resize_window_when_navigation_starts_;
 
   DISALLOW_COPY_AND_ASSIGN(CastWebViewDefault);
 };
diff --git a/chromecast/browser/cast_web_view_factory.cc b/chromecast/browser/cast_web_view_factory.cc
index 9e49e87d089acc..0b9eb9d5cff779 100644
--- a/chromecast/browser/cast_web_view_factory.cc
+++ b/chromecast/browser/cast_web_view_factory.cc
@@ -23,10 +23,11 @@ void CastWebViewFactory::OnPageDestroyed(CastWebView* web_view) {
 std::unique_ptr<CastWebView> CastWebViewFactory::CreateWebView(
     const CastWebView::CreateParams& params,
     CastWebService* web_service,
+    scoped_refptr<content::SiteInstance> site_instance,
     const GURL& initial_url) {
   std::unique_ptr<CastWebView> webview;
-  webview = std::make_unique<CastWebViewDefault>(params, web_service,
-                                                 browser_context_);
+  webview = std::make_unique<CastWebViewDefault>(
+      params, web_service, browser_context_, site_instance);
   if (webview) {
     webview->AddObserver(this);
   }
diff --git a/chromecast/browser/cast_web_view_factory.h b/chromecast/browser/cast_web_view_factory.h
index 725fead66e5a10..6fe95e9cecc6d8 100644
--- a/chromecast/browser/cast_web_view_factory.h
+++ b/chromecast/browser/cast_web_view_factory.h
@@ -16,6 +16,7 @@
 
 namespace content {
 class BrowserContext;
+class SiteInstance;
 }  // namespace content
 
 namespace chromecast {
@@ -30,6 +31,7 @@ class CastWebViewFactory : public CastWebView::Observer {
   virtual std::unique_ptr<CastWebView> CreateWebView(
       const CastWebView::CreateParams& params,
       CastWebService* web_service,
+      scoped_refptr<content::SiteInstance> site_instance,
       const GURL& initial_url);
 
   content::BrowserContext* browser_context() const { return browser_context_; }
diff --git a/chromecast/browser/service/cast_service_simple.cc b/chromecast/browser/service/cast_service_simple.cc
index a961d1a567ffdf..3f7ea0abc3d486 100644
--- a/chromecast/browser/service/cast_service_simple.cc
+++ b/chromecast/browser/service/cast_service_simple.cc
@@ -72,9 +72,10 @@ void CastServiceSimple::StartInternal() {
   params.web_contents_params.enabled_for_dev = true;
   params.window_params.delegate = weak_factory_.GetWeakPtr();
   cast_web_view_ =
-      web_service_->CreateWebView(params, GURL() /* initial_url */);
-  cast_web_view_->cast_web_contents()->LoadUrl(startup_url_);
-  cast_web_view_->window()->GrantScreenAccess();
+      web_service_->CreateWebView(params, nullptr, /* site_instance */
+                                  GURL() /* initial_url */);
+  cast_web_view_->LoadUrl(startup_url_);
+  cast_web_view_->GrantScreenAccess();
   cast_web_view_->InitializeWindow(
       ::chromecast::mojom::ZOrder::APP,
       chromecast::VisibilityPriority::STICKY_ACTIVITY);
@@ -82,7 +83,7 @@ void CastServiceSimple::StartInternal() {
 
 void CastServiceSimple::StopInternal() {
   if (cast_web_view_) {
-    cast_web_view_->cast_web_contents()->ClosePage();
+    cast_web_view_->ClosePage();
   }
   cast_web_view_.reset();
 }
diff --git a/chromecast/browser/test/cast_browser_test.cc b/chromecast/browser/test/cast_browser_test.cc
index be2502e298faf3..5f9300e47e70d4 100644
--- a/chromecast/browser/test/cast_browser_test.cc
+++ b/chromecast/browser/test/cast_browser_test.cc
@@ -64,7 +64,8 @@ content::WebContents* CastBrowserTest::CreateWebView() {
   params.web_contents_params.enabled_for_dev = true;
   params.window_params.delegate = weak_factory_.GetWeakPtr();
   cast_web_view_ =
-      web_service_->CreateWebView(params, GURL() /* initial_url */);
+      web_service_->CreateWebView(params, nullptr, /* site_instance */
+                                  GURL() /* initial_url */);
 
   return cast_web_view_->web_contents();
 }
@@ -76,7 +77,7 @@ content::WebContents* CastBrowserTest::NavigateToURL(const GURL& url) {
   content::WaitForLoadStop(web_contents);
   content::TestNavigationObserver same_tab_observer(web_contents, 1);
 
-  cast_web_view_->cast_web_contents()->LoadUrl(url);
+  cast_web_view_->LoadUrl(url);
 
   same_tab_observer.Wait();
 
diff --git a/chromecast/browser/test/cast_browser_test.h b/chromecast/browser/test/cast_browser_test.h
index 9e12f9ca354d6e..1bcad425d92402 100644
--- a/chromecast/browser/test/cast_browser_test.h
+++ b/chromecast/browser/test/cast_browser_test.h
@@ -35,8 +35,6 @@ class CastBrowserTest : public content::BrowserTestBase,
   CastBrowserTest();
   ~CastBrowserTest() override;
 
-  CastWebView* cast_web_view() const { return cast_web_view_.get(); }
-
   // content::BrowserTestBase implementation:
   void SetUp() final;
   void SetUpCommandLine(base::CommandLine* command_line) override;